VOL-2496 Add "event listen" command to voltctl
Change-Id: I8f1fb34b55f56c8125142ac289e2f19fc170d804
diff --git a/vendor/gopkg.in/jcmturner/gokrb5.v7/client/network.go b/vendor/gopkg.in/jcmturner/gokrb5.v7/client/network.go
new file mode 100644
index 0000000..19d25e6
--- /dev/null
+++ b/vendor/gopkg.in/jcmturner/gokrb5.v7/client/network.go
@@ -0,0 +1,226 @@
+package client
+
+import (
+ "bytes"
+ "encoding/binary"
+ "errors"
+ "fmt"
+ "io"
+ "net"
+ "time"
+
+ "gopkg.in/jcmturner/gokrb5.v7/iana/errorcode"
+ "gopkg.in/jcmturner/gokrb5.v7/messages"
+)
+
+// SendToKDC performs network actions to send data to the KDC.
+func (cl *Client) sendToKDC(b []byte, realm string) ([]byte, error) {
+ var rb []byte
+ if cl.Config.LibDefaults.UDPPreferenceLimit == 1 {
+ //1 means we should always use TCP
+ rb, errtcp := cl.sendKDCTCP(realm, b)
+ if errtcp != nil {
+ if e, ok := errtcp.(messages.KRBError); ok {
+ return rb, e
+ }
+ return rb, fmt.Errorf("communication error with KDC via TCP: %v", errtcp)
+ }
+ return rb, nil
+ }
+ if len(b) <= cl.Config.LibDefaults.UDPPreferenceLimit {
+ //Try UDP first, TCP second
+ rb, errudp := cl.sendKDCUDP(realm, b)
+ if errudp != nil {
+ if e, ok := errudp.(messages.KRBError); ok && e.ErrorCode != errorcode.KRB_ERR_RESPONSE_TOO_BIG {
+ // Got a KRBError from KDC
+ // If this is not a KRB_ERR_RESPONSE_TOO_BIG we will return immediately otherwise will try TCP.
+ return rb, e
+ }
+ // Try TCP
+ r, errtcp := cl.sendKDCTCP(realm, b)
+ if errtcp != nil {
+ if e, ok := errtcp.(messages.KRBError); ok {
+ // Got a KRBError
+ return r, e
+ }
+ return r, fmt.Errorf("failed to communicate with KDC. Attempts made with UDP (%v) and then TCP (%v)", errudp, errtcp)
+ }
+ rb = r
+ }
+ return rb, nil
+ }
+ //Try TCP first, UDP second
+ rb, errtcp := cl.sendKDCTCP(realm, b)
+ if errtcp != nil {
+ if e, ok := errtcp.(messages.KRBError); ok {
+ // Got a KRBError from KDC so returning and not trying UDP.
+ return rb, e
+ }
+ rb, errudp := cl.sendKDCUDP(realm, b)
+ if errudp != nil {
+ if e, ok := errudp.(messages.KRBError); ok {
+ // Got a KRBError
+ return rb, e
+ }
+ return rb, fmt.Errorf("failed to communicate with KDC. Attempts made with TCP (%v) and then UDP (%v)", errtcp, errudp)
+ }
+ }
+ return rb, nil
+}
+
+// dialKDCTCP establishes a UDP connection to a KDC.
+func dialKDCUDP(count int, kdcs map[int]string) (conn *net.UDPConn, err error) {
+ i := 1
+ for i <= count {
+ udpAddr, e := net.ResolveUDPAddr("udp", kdcs[i])
+ if e != nil {
+ err = fmt.Errorf("error resolving KDC address: %v", e)
+ return
+ }
+ conn, err = net.DialUDP("udp", nil, udpAddr)
+ if err == nil {
+ err = conn.SetDeadline(time.Now().Add(5 * time.Second))
+ if err != nil {
+ return
+ }
+ return
+ }
+ i++
+ }
+ err = errors.New("error in getting a UDP connection to any of the KDCs")
+ return
+}
+
+// dialKDCTCP establishes a TCP connection to a KDC.
+func dialKDCTCP(count int, kdcs map[int]string) (conn *net.TCPConn, err error) {
+ i := 1
+ for i <= count {
+ tcpAddr, e := net.ResolveTCPAddr("tcp", kdcs[i])
+ if e != nil {
+ err = fmt.Errorf("error resolving KDC address: %v", e)
+ return
+ }
+ conn, err = net.DialTCP("tcp", nil, tcpAddr)
+ if err == nil {
+ err = conn.SetDeadline(time.Now().Add(5 * time.Second))
+ if err != nil {
+ return
+ }
+ return
+ }
+ i++
+ }
+ err = errors.New("error in getting a TCP connection to any of the KDCs")
+ return
+}
+
+// sendKDCUDP sends bytes to the KDC via UDP.
+func (cl *Client) sendKDCUDP(realm string, b []byte) ([]byte, error) {
+ var r []byte
+ count, kdcs, err := cl.Config.GetKDCs(realm, false)
+ if err != nil {
+ return r, err
+ }
+ conn, err := dialKDCUDP(count, kdcs)
+ if err != nil {
+ return r, err
+ }
+ r, err = cl.sendUDP(conn, b)
+ if err != nil {
+ return r, err
+ }
+ return checkForKRBError(r)
+}
+
+// sendKDCTCP sends bytes to the KDC via TCP.
+func (cl *Client) sendKDCTCP(realm string, b []byte) ([]byte, error) {
+ var r []byte
+ count, kdcs, err := cl.Config.GetKDCs(realm, true)
+ if err != nil {
+ return r, err
+ }
+ conn, err := dialKDCTCP(count, kdcs)
+ if err != nil {
+ return r, err
+ }
+ rb, err := cl.sendTCP(conn, b)
+ if err != nil {
+ return r, err
+ }
+ return checkForKRBError(rb)
+}
+
+// sendUDP sends bytes to connection over UDP.
+func (cl *Client) sendUDP(conn *net.UDPConn, b []byte) ([]byte, error) {
+ var r []byte
+ defer conn.Close()
+ _, err := conn.Write(b)
+ if err != nil {
+ return r, fmt.Errorf("error sending to (%s): %v", conn.RemoteAddr().String(), err)
+ }
+ udpbuf := make([]byte, 4096)
+ n, _, err := conn.ReadFrom(udpbuf)
+ r = udpbuf[:n]
+ if err != nil {
+ return r, fmt.Errorf("sending over UDP failed to %s: %v", conn.RemoteAddr().String(), err)
+ }
+ if len(r) < 1 {
+ return r, fmt.Errorf("no response data from %s", conn.RemoteAddr().String())
+ }
+ return r, nil
+}
+
+// sendTCP sends bytes to connection over TCP.
+func (cl *Client) sendTCP(conn *net.TCPConn, b []byte) ([]byte, error) {
+ defer conn.Close()
+ var r []byte
+ /*
+ RFC https://tools.ietf.org/html/rfc4120#section-7.2.2
+ Each request (KRB_KDC_REQ) and response (KRB_KDC_REP or KRB_ERROR)
+ sent over the TCP stream is preceded by the length of the request as
+ 4 octets in network byte order. The high bit of the length is
+ reserved for future expansion and MUST currently be set to zero. If
+ a KDC that does not understand how to interpret a set high bit of the
+ length encoding receives a request with the high order bit of the
+ length set, it MUST return a KRB-ERROR message with the error
+ KRB_ERR_FIELD_TOOLONG and MUST close the TCP stream.
+ NB: network byte order == big endian
+ */
+ var buf bytes.Buffer
+ err := binary.Write(&buf, binary.BigEndian, uint32(len(b)))
+ if err != nil {
+ return r, err
+ }
+ b = append(buf.Bytes(), b...)
+
+ _, err = conn.Write(b)
+ if err != nil {
+ return r, fmt.Errorf("error sending to KDC (%s): %v", conn.RemoteAddr().String(), err)
+ }
+
+ sh := make([]byte, 4, 4)
+ _, err = conn.Read(sh)
+ if err != nil {
+ return r, fmt.Errorf("error reading response size header: %v", err)
+ }
+ s := binary.BigEndian.Uint32(sh)
+
+ rb := make([]byte, s, s)
+ _, err = io.ReadFull(conn, rb)
+ if err != nil {
+ return r, fmt.Errorf("error reading response: %v", err)
+ }
+ if len(rb) < 1 {
+ return r, fmt.Errorf("no response data from KDC %s", conn.RemoteAddr().String())
+ }
+ return rb, nil
+}
+
+// checkForKRBError checks if the response bytes from the KDC are a KRBError.
+func checkForKRBError(b []byte) ([]byte, error) {
+ var KRBErr messages.KRBError
+ if err := KRBErr.Unmarshal(b); err == nil {
+ return b, KRBErr
+ }
+ return b, nil
+}